This invention concerns the head of an electrical toothbrush that is connected to the handle by a housing case which has a vertical and a horizontal drill-hole; an axle, connectable with a shaft of the handle, that can be fit into the vertical drill hole such that it is turnable; a brush head that can be fit into the horizontal drill hole such that it is turnable; transfer elements to transfer the rotation of the axle to the brush head. Such toothbrush parts are widely available nowadays. All known brush parts specifically go with and fit their corresponding handles. Thus, brush parts of a different make cannot be exchanged for that of another, but fit only a given handle. Brush parts on the market consist of different individual parts made from various materials. Usually they are part plastic and part metal. Because of the large number of components, these parts are difficult to assemble and costs are relatively high. Furthermore, the known brush parts are designed such that they cannot be repaired if they break but have to be replaced as a whole.
Growth of microorganisms is facilitated by the moisture remaining in some parts of the toothbrush. To counteract this, bristles are made of oligo-dynamic materials, generally as galvanic coating or mounting devices.
DE 39 37 853 A1 describes an electrical toothbrush that has a handle with an electrical drive inside the drive shaft, as well as a brush part containing an axle in its housing. The handle is connected to the brush head via connecting parts in order to attach the brush to the handle and to establish an attachment between the drive shaft and the axle.
DE 39 37 853 A1 discloses an attachment of the brush part to the handle in axial and radial direction by separate connecting parts. The connecting parts of the drive shaft and the axle, and the connecting parts of the handle and the neck of the brush interact. The axial connection is established by lockable elements of the axle, which act on a counter bearing of the drive shaft. The radial connection works based on a special profile of the housing and the head of the handle.
It is known from DE 33 46 758 A1 that there is supposed to be a bevel gear connection or a toothed rack gear between the brush head and the axle of the brush part.
Commonly available are also complicated tilting lever constructs that transfer the rotation of the axle to the brush head. These constructs are not only difficult to assemble but consist of many individual parts.
A further disadvantage of the known brush heads is the fact that tartar is difficult to remove with rotating bristles.
One of the tasks of this invention is to design a simpler brush part for an electrical toothbrush that can be produced and assembled easier and shows better cleaning action compared to the known brush parts.
In particular, the number of individual components should be reduced. Furthermore, a brush part should be constructed such that it will fit various brush handles of different makes without an additional adapter.
The invention is a brush part according to claim 1.
The basic idea of this invention is that the brush head is bedded in a horizontal drill hole by a lockable sleeve bearing. This sleeve bearing has a roughened surface allowing for an axial oscillation.
An essential advantage of this invented brush part is that the number of individual components is reduced through integration. The use of one or more sleeve bearings simplifies the assembly. The removal of tartar is greatly enhanced by the axial oscillatory movement that adds to the radial movement of the brush head. This results in a thrusting action of the bristles in such a way that the tartar gets broken up and can be removed easier.
Furthermore, the individual components of the invented brush part can be designed to be replaceable such that, for example, the brush head can be exchanged without having to replace the complete brush part.
The sub-claims describe improvements and developments that can be of advantage for the in claim 1 described brush part.
An additional idea of this invention is to push the brush part over the drive shaft of the handle via a hollow axle. The brush part can be attached in axial direction onto an overhanging housing component using a clamping plug that is movable in axial direction and is moldable due to locking elements. The rotary movement of the metal axle of the handle is transferred by attachment of the axle of the brush part. The radial and axial fixation of the brush part is achieved by attachment via the elastic, moldable plug. Thus, no connecting elements are needed between the metal axle of the handle and the axle of the brush part. Another advantage of this invention is thatxe2x80x94should it become necessary to replace the brush partxe2x80x94the customer can exchange individual parts separately without having to replace the entire unit.